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European Physical Journal C: Particles and Fields 72 (2012) 2100
Measurement of psi(2S) meson production in pp collisions at sqrt(s)=7 TeV
R. Aaij, S. Barsuk1, O. Callot1, J. He1, B. Jean-Marie1, J. Lefrançois1, F. Machefert1, A. Martin Sanchez1, M. Nicol1, P. Robbe1, M.-H. Schune1, B. Viaud1, I. Videau1, E. Ben-Haim2, M. Benayoun2, P. David2, L. Del Buono2, A. Martens2, Z J Ajaltouni3, O. Deschamps3, P. Henrard3, M. Jahjah Hussein3, R. Lefèvre3, L. Li Gioi3, S. Monteil3, V. Niess3, P. Perret3, D. Roa Romero3, K. Sobczak3, C. Adrover4, E. Aslanides4, J. Cogan4, B. Khanji4, R. Legac4, O. Leroy4, G. Mancinelli4, E. Maurice4, M. Perrin-Terrin4, M. Sapunov4, J. Serrano4, A. Tsaregorodtsev4, I. De Bonis5, D. Decamp5, Ph. Ghez5, P. Hopchev5, J.-P. Lees5, I.V. Machikhiliyan5, M.-N. Minard5, B. Pietrzyk5, S. T'Jampens5, V. Tisserand5, E. Tournefier5
LHCb Collaboration(s)
(2012)

The differential cross-section for the inclusive production of psi(2S) mesons in pp collisions at sqrt(s)=7 TeV has been measured with the LHCb detector. The data sample corresponds to an integrated luminosity of 36 pb-1. The psi(2S) mesons are reconstructed in the decay channels psi(2S) -> mu+ mu- and psi(2S) -> J/psi pi+ pi-, with the J/psi meson decaying into two muons. Results are presented both for promptly produced psi(2S) mesons and for those originating from b-hadron decays. In the kinematic range pT(psi(2S)) <= 16 GeV/c and 2 < y(psi(2S)) <= 4.5 we measure 1.44 +- 0.01 +- 0.12+0.2-0.4 mub for prompt psi(2S) production and 0.25 +- 0.01 +- 0.02 mub for psi(2S) from b-hadron decays, where the last uncertainty on the prompt cross-section is due to the unknown psi(2S) polarization. Recent QCD calculations are found to be in good agreement with our measurements. Combining the present result with the LHCb J/psi measurements we determine the inclusive branching fraction B(b -> psi(2S) X) = (2.73 +- 0.06 +- 0.16 +- 0.24) x 10^(-3), where the last uncertainty is due to the B(b -> J/psi X), B(J/psi -> mu+ mu-) and B(psi(2S) -> e+ e-) branching fraction uncertainties.
1 :  LAL - Laboratoire de l'Accélérateur Linéaire
2 :  LPNHE - Laboratoire de Physique Nucléaire et de Hautes Énergies
3 :  LPC - Laboratoire de Physique Corpusculaire [Clermont-Ferrand]
4 :  CPPM - Centre de Physique des Particules de Marseille
5 :  LAPP - Laboratoire d'Annecy le Vieux de Physique des Particules
Physique/Physique des Hautes Energies - Expérience
Lien vers le texte intégral : 
http://fr.arXiv.org/abs/1204.1258